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Grand Isle is a town in Grand Isle county, Vermont. It was formed in 1769 in N.Y. from the following county/ies: Chittenden, though the following competing claims for its origins are Vt. 1779. It has used the following other name(s): Two Heros/Middle Hero. The probate and court district for Grand Isle is Grand Isle. For more information, contact the town at 9 Hyde Rd., P.O. Box 49, Grand Isle 05458. On the attached map, Grand Isle is shown as 4 in Grand Isle county.